Reference gene recommendations and PACAP receptor expression in murine sympathetic ganglia of the autonomic nervous system that innervate adipose tissues after chronic cold exposure.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is an important regulator of the stress response in mammals, influencing both the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS). PACAP has been reported to influence energy homeostasis, including adaptive thermogenesis, an energy burning process in adipose tissue regulated by the SNS in response to cold stress and overfeeding. While research suggests PACAP acts centrally at the level of the hypothalamus, knowledge of PACAP's role within the sympathetic nerves innervating adipose tissues in response to metabolic stressors is limited. This work shows, for the first time, gene expression of PACAP receptors in stellate ganglia and highlights some differential expression with housing temperature. Additionally, we present our dissection protocol, analysis of tyrosine hydroxylase gene expression as a molecular biomarker for catecholamine producing tissue and recommend three stable reference genes for the normalization of quantitative real time-polymerase chain reaction (qRT-PCR) data when working with this tissue. This study adds to information about neuropeptide receptor expression in peripheral ganglia of the sympathetic nervous system innervating adipose tissue and provides insight into PACAP's role in the regulation of energy metabolism.

Downregulation of Bmal1 Expression in Celiac Ganglia Protects against Hepatic Ischemia-Reperfusion Injury.

Hepatic ischemia-reperfusion injury (HIRI) significantly contributes to liver dysfunction following liver transplantation and hepatectomy. However, the role of the celiac ganglion (CG) in HIRI remains unclear. Adeno-associated virus was used to silence Bmal1 expression in the CG of twelve beagles that were randomly assigned to the Bmal1 knockdown group (KO-Bmal1) and the control group. After four weeks, a canine HIRI model was established, and CG, liver tissue, and serum samples were collected for analysis. The virus significantly downregulated Bmal1 expression in the CG. Immunofluorescence staining confirmed a lower proportion of c-fos+ and NGF+ neurons in TH+ cells in the KO-Bmal1 group than in the control group. The KO-Bmal1 group exhibited lower Suzuki scores and serum ALT and AST levels than the control group. Bmal1 knockdown significantly reduced liver fat reserve, hepatocyte apoptosis, and liver fibrosis, and it increased liver glycogen accumulation. We also observed that Bmal1 downregulation inhibited the hepatic neurotransmitter norepinephrine, neuropeptide Y levels, and sympathetic nerve activity in HIRI. Finally, we confirmed that decreased Bmal1 expression in CG reduces TNF-α, IL-1ß, and MDA levels and increases GSH levels in the liver. The downregulation of Bmal1 expression in CG suppresses neural activity and improves hepatocyte injury in the beagle model after HIRI.

Interplay between nitric oxide and gonadotrophin-releasing hormone in the neuromodulation of the corpus luteum during late pregnancy in the rat.

BACKGROUND: Nitric oxide and GnRH are biological factors that participate in the regulation of reproductive functions. To our knowledge, there are no studies that link NO and GnRH in the sympathetic ganglia. Thus, the aim of the present work was to investigate the influence of NO on GnRH release from the coeliac ganglion and its effect on luteal regression at the end of pregnancy in the rat. METHODS: The ex vivo system composed by the coeliac ganglion, the superior ovarian nerve, and the ovary of rats on day 21 of pregnancy was incubated for 180 min with the addition, into the ganglionic compartment, of L-NG-nitro arginine methyl ester (L-NAME), a non-selective NO synthase inhibitor. The control group consisted in untreated organ systems. RESULTS: The addition of L-NAME in the coeliac ganglion compartment decreased NO as well as GnRH release from the coeliac ganglion. In the ovarian compartment, and with respect to the control group, we observed a reduced release of GnRH, NO, and noradrenaline, but an increased production of progesterone, estradiol, and expression of their limiting biosynthetic enzymes, 3ß-HSD and P450 aromatase, respectively. The inhibition of NO production by L-NAME in the coeliac ganglion compartment also reduced luteal apoptosis, lipid peroxidation, and nitrotyrosine, whereas it increased the total antioxidant capacity within the corpora lutea. CONCLUSION: Collectively, the results indicate that NO production by the coeliac ganglion modulates the physiology of the ovary and luteal regression during late pregnancy in rats.

Generation, Characterization, and Application of Inducible Proliferative Adult Human Epicardium-Derived Cells.

RATIONALE: In recent decades, the great potential of human epicardium-derived cells (EPDCs) as an endogenous cell source for cardiac regeneration has been recognized. The limited availability and low proliferation capacity of primary human EPDCs and phenotypic differences between EPDCs obtained from different individuals hampers their reproducible use for experimental studies. AIM: To generate and characterize inducible proliferative adult human EPDCs for use in fundamental and applied research. METHODS AND RESULTS: Inducible proliferation of human EPDCs was achieved by doxycycline-controlled expression of simian virus 40 large T antigen (LT) with a repressor-based lentiviral Tet-On system. In the presence of doxycycline, these inducible EPDCs (iEPDCs) displayed high and long-term proliferation capacity. After doxycycline removal, LT expression ceased and the iEPDCs regained their cuboidal epithelial morphology. Similar to primary EPDCs, iEPDCs underwent an epithelial-to-mesenchymal transition (EMT) after stimulation with transforming growth factor ß3. This was confirmed by reverse transcription-quantitative polymerase chain reaction analysis of epithelial and mesenchymal marker gene expression and (immuno) cytochemical staining. Collagen gel-based cell invasion assays demonstrated that mesenchymal iEPDCs, like primary EPDCs, possess increased invasion and migration capacities as compared to their epithelial counterparts. Mesenchymal iEPDCs co-cultured with sympathetic ganglia stimulated neurite outgrowth similarly to primary EPDCs. CONCLUSION: Using an inducible LT expression system, inducible proliferative adult human EPDCs were generated displaying high proliferative capacity in the presence of doxycycline. These iEPDCs maintain essential epicardial characteristics with respect to morphology, EMT ability, and paracrine signaling following doxycycline removal. This renders iEPDCs a highly useful new in vitro model for studying human epicardial properties.

Neuromodulatory effect of GnRH from coeliac ganglion on luteal regression in the late pregnant rat.

The GnRH/GnRH receptor system has been found in several extrapituitary tissues, although its physiological significance has not yet been well established. Taking into account that the peripheral neural system can act as a modulator of pregnancy corpus luteum, the objective was to physiologically investigate the presence of the GnRH system in coeliac ganglion (CG) and to analyse its possible involvement in luteal regression through the superior ovarian nerve (SON) at the end of pregnancy in the rat. The integrated ex vivo CG-SON-Ovary system of rats on day 21 of pregnancy was used. Cetrorelix (CTX), a GnRH receptor antagonist, was added into the ganglionic compartment while the control systems were untreated. Ganglionic GnRH release was detected under basal conditions. Then, the CTX addition in CG increased it, which would indicate the blockade of the receptor. In turn, CTX in CG caused an increase in ovarian progesterone release. Furthermore, the luteal cells showed an increase in the expression of Hsd3b1 and a decrease in the expression of Akr1c3 (progesterone synthesis and degradation enzymes, respectively), reduced TUNEL staining according to an increase in the antioxidant defence system activity and low lipid peroxide levels. The ovarian and ganglionic nitric oxide (NO) release increased, while the luteal nitrotyrosine content, measured as nitrosative stress marker, decreased. CTX in CG decreased the ovarian noradrenaline release. The present study provides evidence that GnRH from CG may trigger neuronal signals that promote the luteal regression in late pregnancy by affecting the release of NO and noradrenaline in the ovary.

Human epicardium-derived cells reinforce cardiac sympathetic innervation.

RATIONALE: After cardiac damage, excessive neurite outgrowth (sympathetic hyperinnervation) can occur, which is related to ventricular arrhythmias/sudden cardiac death. Post-damage reactivation of epicardium causes epicardium-derived cells (EPDCs) to acquire a mesenchymal character, contributing to cardiac regeneration. Whether EPDCs also contribute to cardiac re/hyperinnervation, is unknown. AIM: To investigate whether mesenchymal EPDCs influence cardiac sympathetic innervation. METHODS AND RESULTS: Sympathetic ganglia were co-cultured with mesenchymal EPDCs and/or myocardium, and neurite outgrowth and sprouting density were assessed. Results showed a significant increase in neurite density and directional (i.e. towards myocardium) outgrowth when ganglia were co-cultured with a combination of EPDCs and myocardium, as compared to cultures with EPDCs or myocardium alone. In absence of myocardium, this outgrowth was not directional. Neurite differentiation of PC12 cells in conditioned medium confirmed these results via a paracrine effect, in accordance with expression of neurotrophic factors in myocardial explants co-cultured with EPDCs. Of interest, EPDCs increased the expression of nerve growth factor (NGF) in cultured, but not in fresh myocardium, possibly due to an "ischemic state" of cultured myocardium, supported by TUNEL and Hif1α expression. Cardiac tissues after myocardial infarction showed robust NGF expression in the infarcted, but not remote area. CONCLUSION: Neurite outgrowth and density increases significantly in the presence of EPDCs by a paracrine effect, indicating a new role for EPDCs in the occurrence of sympathetic re/hyperinnervation after cardiac damage.

18F-Fluciclovine Uptake in Celiac Ganglia: A Pitfall in Prostate Cancer PET Imaging.

We present 4 cases of patients who underwent F-fluciclovine PET for prostate cancer demonstrating physiologic uptake in the celiac ganglia, which could be mistaken for metastatic lymphadenopathy if the celiac ganglia have a nodular configuration and uptake higher than bone marrow. Uptake in celiac, cervical, and sacral ganglia has been reported previously as an important pitfall in Ga-PSMA-HBED-CC PET for prostate cancer. In our patients, only celiac ganglion uptake was visualized. Advances in PET scanner technology may cause physiologic uptake of F-fluciclovine in celiac ganglia to become more visually distinguishable from muscular uptake in adjacent diaphragmatic crura.

Immunohistochemical analysis of the mouse celiac ganglion: An integrative relay station of the peripheral nervous system.

Celiac ganglia are important sites of signal integration and transduction. Their complex neurochemical anatomy has been studied extensively in guinea pigs but not in mice. The goal of this study was to provide detailed neurochemical characterization of mouse celiac ganglia and noradrenergic nerves in two target tissues, spleen and stomach. A vast majority of mouse celiac neurons express a noradrenergic phenotype, which includes tyrosine hydroxylase (TH), vesicular monoamine transporter 2, and the norepinephrine transporter. Over 80% of these neuron also express neuropeptide Y (NPY), and this coexpression is maintained by dissociated neurons in culture. Likewise, TH and NPY were colocalized in noradrenergic nerves throughout the spleen and in stomach blood vessels. Somatostatin was not detected in principal neurons but did occur in small, TH-negative cells presumed to be interneurons and in a few varicose nerve fibers. Cholinergic nerves provided the most abundant input to the ganglia, and small percentages of these also contained nitric oxide synthase or vasoactive intestinal polypeptide. A low-to-moderate density of nerves also stained separately for the latter markers. Additionally, nerve bundles and varicose nerve fibers containing the sensory neuropeptides, calcitonin gene-related polypeptide, and substance P, occurred at variable density throughout the ganglia. Collectively, these findings demonstrate that principal neurons of mouse celiac ganglia have less neurochemical diversity than reported for guinea pig and other species but receive input from nerves expressing an array of neurochemical markers. This profile suggests celiac neurons integrate input from many sources to influence target tissues by releasing primarily norepinephrine and NPY.

Regional Differences in the Contributions of TNF Reverse and Forward Signaling to the Establishment of Sympathetic Innervation.

Members of the TNF and TNF receptor superfamilies acting by both forward and reverse signaling are increasingly recognized as major physiological regulators of axon growth and tissue innervation in development. Studies of the experimentally tractable superior cervical ganglion (SCG) neurons and their targets have shown that only TNF reverse signaling, not forward signaling, is a physiological regulator of sympathetic innervation. Here, we compared SCG neurons and their targets with prevertebral ganglion (PVG) neurons and their targets. Whereas all SCG targets were markedly hypoinnervated in both TNF-deficient and TNFR1-deficient mice, PVG targets were not hypoinnervated in these mice and one PVG target, the spleen, was significantly hyperinnervated. These in vivo regional differences in innervation density were related to in vitro differences in the responses of SCG and PVG neurons to TNF reverse and forward signaling. Though TNF reverse signaling enhanced SCG axon growth, it did not affect PVG axon growth. Whereas activation of TNF forward signaling in PVG axons inhibited growth, TNF forward signaling could not be activated in SCG axons. These latter differences in the response of SCG and PVG axons to TNF forward signaling were related to TNFR1 expression, whereas PVG axons expressed TNFR1, SCG axons did not. These results show that both TNF reverse and forward signaling are physiological regulators of sympathetic innervation in different tissues.

CD40L reverse signaling suppresses prevertebral sympathetic axon growth and tissue innervation.

CD40-activated CD40L reverse signaling is a major physiological regulator of the growth of neural processes in the developing nervous system. Previous work on superior cervical ganglion (SCG) neurons of the paravertebral sympathetic chain has shown that CD40L reverse signaling enhances NGF-promoted axon growth and tissue innervation. Here we show that CD40L reverse signaling has the opposite function in prevertebral ganglion (PVG) sympathetic neurons. During a circumscribed perinatal window of development, PVG neurons cultured from Cd40-/- mice had substantially larger, more exuberant axon arbors in the presence of NGF than PVG neurons cultured from wild-type mice. Tissues that receive their sympathetic innervation from PVG neurons were markedly hyperinnervated in Cd40-/- mice compared with wild-type mice. The exuberant axonal growth phenotype of cultured CD40-deficient perinatal PVG neurons was pared back to wild-type levels by activating CD40L reverse signaling with a CD40-Fc chimeric protein, but not by activating CD40 forward signaling with CD40L. The co-expression of CD40 and CD40L in PVG neurons suggests that these proteins engage in an autocrine signaling loop in these neurons. Our work shows that CD40L reverse signaling is a physiological regulator of NGF-promoted sympathetic axon growth and tissue innervation with opposite effects in paravertebral and prevertebral neurons.

The production of nitric oxide in the coeliac ganglion modulates the effect of cholinergic neurotransmission on the rat ovary during the preovulatory period.

The aim of the present work was to investigate whether the nitric oxide produced by the nitric oxide/nitric oxide synthase (NO/NOS) system present in the coeliac ganglion modulates the effects of cholinergic innervation on oxidative status, steroidogenesis and apoptotic mechanisms that take place in the rat ovary during the first proestrous. An ex vivo Coeliac Ganglion- Superior Ovarian Nerve- Ovary (CG-SON-O) system was used. Cholinergic stimulation of the CG was achieved by 10-6 M Acetylcholine (Ach). Furthermore, 400 µM Aminoguanidine (AG) - an inhibitor of inducible-NOS was added in the CG compartment in absence and presence of Ach. It was found that Ach in the CG compartment promotes apoptosis in ovarian tissue, probably due to the oxidative stress generated. AG in the CG compartment decreases the release of NO and progesterone, and increases the release of estradiol from the ovary. The CG co-treatment with Ach and AG counteracts the effects of the ganglionic cholinergic agonist on ovarian oxidative stress, increases hormone production and decreases Fas mRNA expression. These results suggest that NO is an endogenous modulator of cholinergic neurotransmission in CG, with implication in ovarian steroidogenesis and the apoptotic mechanisms that take place in the ovary during the preovulatory period in rats.

Temporal requirements for ISL1 in sympathetic neuron proliferation, differentiation, and diversification.

Malformations of the sympathetic nervous system have been associated with cardiovascular instability, gastrointestinal dysfunction, and neuroblastoma. A better understanding of the factors regulating sympathetic nervous system development is critical to the development of potential therapies. Here, we have uncovered a temporal requirement for the LIM homeodomain transcription factor ISL1 during sympathetic nervous system development by the analysis of two mutant mouse lines: an Isl1 hypomorphic line and mice with Isl1 ablated in neural crest lineages. During early development, ISL1 is required for sympathetic neuronal fate determination, differentiation, and repression of glial differentiation, although it is dispensable for initial noradrenergic differentiation. ISL1 also plays an essential role in sympathetic neuron proliferation by controlling cell cycle gene expression. During later development, ISL1 is required for axon growth and sympathetic neuron diversification by maintaining noradrenergic differentiation, but repressing cholinergic differentiation. RNA-seq analyses of sympathetic ganglia from Isl1 mutant and control embryos, together with ISL1 ChIP-seq analysis on sympathetic ganglia, demonstrated that ISL1 regulates directly or indirectly several distinct signaling pathways that orchestrate sympathetic neurogenesis. A number of genes implicated in neuroblastoma pathogenesis are direct downstream targets of ISL1. Our study revealed a temporal requirement for ISL1 in multiple aspects of sympathetic neuron development, and suggested Isl1 as a candidate gene for neuroblastoma.

Changes in Somatostatin-Like Immunoreactivity in the Sympathetic Neurons Projecting to the Prepyloric Area of the Porcine Stomach Induced by Selected Pathological Conditions.

The aim of the present study was to define changes in the expression of somatostatin (SOM) in the sympathetic perikarya innervating the porcine stomach prepyloric area during acetylsalicylic-acid-induced gastritis (ASA) and experimentally induced hyperacidity (HCL) and following partial stomach resection (RES). On day 1, the stomachs were injected with neuronal retrograde tracer Fast Blue (FB). Animals in the ASA group were given acetylsalicylic acid orally for 21 days. On the 22nd day after FB injection, partial stomach resection was performed in RES animals. On day 23, HCL animals were intragastrically given 5 ml/kg of body weight of a 0.25 M aqueous solution of hydrochloric acid. On day 28, all pigs were euthanized. Then, 14-µm thick cryostat sections of the coeliac-superior mesenteric ganglion (CSMG) complexes were processed for routine double-labelling immunofluorescence. All pathological conditions studied resulted in upregulation of SOM-like (SOM-LI) immunoreactivity (from 14.97 ± 1.57% in control group to 33.72 ± 4.39% in the ASA group, to 39.02 ± 3.65% in the RES group, and to 29.63 ± 0.85% in the HCL group). The present studies showed that altered expression of SOM occurs in sympathetic neurons supplying the prepyloric area of the porcine stomach during adaptation to various pathological insults.

Coordinate expression of pan-neuronal and functional signature genes in sympathetic neurons.

Neuron subtypes of the mature nervous system differ in the expression of characteristic marker genes while they share the expression of generic neuronal genes. The regulatory logic that maintains subtype-specific and pan-neuronal genes is not well understood. To begin to address this issue, we analyze RNA sequencing results from whole sympathetic ganglia and single sympathetic neurons in the mouse. We focus on gene products involved in the neuronal cytoskeleton, neurotransmitter synthesis and storage, transmitter release and reception and electrical information processing. We find a particular high correlation in the expression of stathmin 2 and several members of the tubulin beta family, classical pan-neuronal markers. Noradrenergic transmitter-synthesizing enzymes and transporters are also well correlated in their cellular transcript levels. In addition, noradrenergic marker transcript levels correlate well with selected pan-neuronal markers. Such a correlation in transcript levels is also seen between a number of selected ion channel, receptor and synaptic protein genes. These results provide the foundation for the analyses of the coordinated expression of downstream target genes in nerve cells.

[Developmental changes of neurotransmitter properties in sympathetic neurons].

Neurochemical composition of metasympathetic nervous system is characterized by a large variation. The main part of the intramural ganglionic neurons is cholinergic. Along with cholinergic neurons, there are ganglionic neurons containing serotonin, histamine, GABA, and several peptides: cholecystokinin, dynorphin, enkephalin, galanin, gastrin-releasing peptide (bombesin in mammals), neuropeptide Y, neurotensin, somatostatin, tachykinins, neurokinin A, vasoactive intestinal polypeptide and calcitonin gene related peptide. Gases as NO, CO, H2S, also act as neurotransmitters. Separate groups of neurons differ in the content of neuronal calcium-binding proteins, such as calbindin, calretinin and parvalbumin and neurofilaments: low molecular weight, a medium molecular weight and high molecular weight. Neurons of the enteric ganglia are the most different by their neurochemistry. There is a species difference in the ganglia of large animals and humans there are more combinations of chemical transmitters. Synthesis of neurotransmitters takes place even in the embryonic period and by the time of birth the most of neurons contain acetylcholine. In postnatal ontogenesis, the proportion of neurons expressing the NO-synthase decreases in the enteric and cardiac intramural ganglionic neurons. The functional significance of these changes is unclear.

Short-term facilitation and depression of transmitter release at amphibian sympathetic ganglionic cells - Mathematical/computational modeling.

There have been few investigations of the short-term plasticity of synaptic transmission at amphibian sympathetic ganglionic cells where the frequency of miniature excitatory postsynaptic potentials is too low to measure an accurate quantum size. This has made it difficult to investigate the mechanism of synaptic transmission at the ganglionic cells by quantal analysis. A theoretical equation, therefore, is proposed. This equation is based on the premise that transmitter release is due to the product of two factors: intracellular calcium ([Ca2+]i) and acetylcholine (ACh), which is a readily releasable transmitter. The equation accounts for the mechanism of synaptic facilitation and depression of transmitter release at the ganglionic cells in the paired-pulse experiments. The purpose of the present experiment is to investigate whether the equation accounts for the mechanism of short-term plasticity of synaptic transmission produced by a train of pulses at the ganglionic cells. Trains of excitatory postsynaptic current (EPSC) were recorded, and the ratios of the nth EPSC induced by the nth pulse to the initial EPSC were analyzed by the equation. The results indicated that the mechanism of short-term facilitation and depression was interpreted by the equation, which met the following two requirements: [Ca2+]i consisting of two components of residual Ca2+ and the mobilization rate of ACh which accelerated as stimulus frequencies increased. The findings were consistent with those clarified by the quantal analysis. It is suggested that the theoretical equation is also useful for the investigation of the effect of chemical substances on synaptic transmission.

Uptake in sympathetic ganglia on 68 Ga-PSMA-HBED PET/CT: A potential pitfall in scan interpretation.

INTRODUCTION: The aim of this study was to assess the frequency of PSMA-HBED uptake in coeliac and stellate ganglia in patients presenting for PSMA-HBED PET/CT scan. METHODS: Prostate-specific membrane antigen-HBED PET/CT scans of 100 consecutive patients were analysed. Coeliac and stellate ganglia were identified by their anatomical location. PSMA-HBED uptake in these ganglia was recorded as either present or absent. If present, the SUVmax value for each ganglion was measured and compared to SUVmax of mediastinal blood pool. RESULTS: Of the 100 patients, 45 had PSMA-HBED uptake in the right coeliac ganglion and 81 had PSMA-HBED uptake in the left coeliac ganglion. The mean SUVmax for the right coeliac ganglion was 2.6 (range 1.2-4.0) and for the left, 2.7 (range 1.2-6.5). An SUVmax 1.5 times greater than that of mediastinal blood pool activity was found in 25 of right and 47 of left coeliac ganglia. Stellate ganglion uptake of PSMA-HBED was identified in 54 of right and 74 of left stellate ganglia. The mean SUVmax for the right and left stellate ganglia were 2.2 (range 1.6-3.6) and 2.4 (range 1.4-4.2) respectively. An SUVmax 1.5 times greater than that of mediastinal blood pool activity was found in 12 of right and 32 of left coeliac ganglia. CONCLUSION: Uptake in coeliac and stellate ganglia is a frequent finding on PSMA-HBED PET/CT imaging. Often this uptake can be sufficiently high to cause potential diagnostic confusion. It is important to be aware of this physiologic uptake to avoid incorrect diagnosis of metastatic prostate carcinoma.

Neuromodulatory effect of oestradiol in the metabolism of ovarian progesterone and oestradiol during dioestrus II: participation of the superior mesenteric ganglion.

The aims of the present study were to determine: (1) whether oestradiol (E2) in the superior mesenteric ganglion (SMG) modifies the release of ovarian progesterone (P4), androstenedione (A2) and E2, the activity and gene expression of 3ß-hydroxysteroid dehydrogenase (3ß-HSD) and 20α-HSD and the expression of P450 aromatase (Cyp19a1) and (2) whether any such modifications are related to changes in ovarian nitric oxide (NO) and noradrenaline (NA) levels during dioestrus II. Using an ex vivo SMG-ovarian nervous plexus-ovary system, ovarian P4 release was measured following the addition E2 plus tamoxifen (Txf) (10-6M) to the ganglion, whereas A2, E2, NA and NO were measured following the addition of E2 alone. Steroids were measured by radioimmunoassay, NA concentrations were determined by HPLC and gene expression was evaluated using reverse transcription-polymerase chain reaction. Oestradiol in the ganglion decreased ovarian P4, E2 and NA release, as well as 3ß-HSD activity, but increased the release of A2 and nitrites, as well as the 20α-HSD expression and its activity. No changes were observed in Cyp19a1 gene expression. The addition of E2 plus Txf to the ganglion reversed the effects of E2 alone. The action of oestradiol in SMG favours the beginning of functional luteolysis, due to an increase in NO release and a decrease in NA in the ovary. These results may help elucidate the role of E2 in hormone-dependent pathologies in women.

The Influence of Tetrodotoxin (TTX) on the Distribution and Chemical Coding of Caudal Mesenteric Ganglion (CaMG) Neurons Supplying the Porcine Urinary Bladder.

The treatment of micturition disorders creates a serious problem for urologists. Recently, new therapeutic agents, such as neurotoxins, are being considered for the therapy of urological patients. The present study investigated the chemical coding of caudal mesenteric ganglion (CaMG) neurons supplying the porcine urinary bladder after intravesical instillation of tetrodotoxin (TTX). The CaMG neurons were visualized with retrograde tracer Fast blue (FB) and their chemical profile was disclosed with double-labeling immunohistochemistry using antibodies against tyrosine hydroxylase (TH), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), somatostatin (SOM), calbindin (CB), galanin (GAL) and neuronal nitric oxide synthase (nNOS). It was found that in both the control (n = 6) and TTX-treated pigs (n = 6), the vast majority (92.6% ± 3.4% and 88.8% ± 2%, respectively) of FB-positive (FB+) nerve cells were TH+. TTX instillation caused a decrease in the number of FB+/TH+ neurons immunopositive to NPY (88.9% ± 5.3% in the control animals vs. 10.6% ± 5.3% in TTX-treated pigs) or VIP (1.7% ± 0.6% vs. 0%), and an increase in the number of FB+/TH+ neurons immunoreactive to SOM (8.8% ± 1.6% vs. 39% ± 12.8%), CB (1.8% ± 0.7% vs. 12.6% ± 2.7%), GAL (1.7% ± 0.8% vs. 10.9% ± 2.6%) or nNOS (0% vs. 1.1% ± 0.3%). The present study is the first to suggest that TTX modifies the chemical coding of CaMG neurons supplying the porcine urinary bladder.